CN116357383A - Multi-layer-multi-angle old goaf grouting filling method - Google Patents
Multi-layer-multi-angle old goaf grouting filling method Download PDFInfo
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- CN116357383A CN116357383A CN202310401922.2A CN202310401922A CN116357383A CN 116357383 A CN116357383 A CN 116357383A CN 202310401922 A CN202310401922 A CN 202310401922A CN 116357383 A CN116357383 A CN 116357383A
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- 238000000034 method Methods 0.000 title claims abstract description 44
- 238000005553 drilling Methods 0.000 claims abstract description 47
- 239000002002 slurry Substances 0.000 claims abstract description 13
- 239000003245 coal Substances 0.000 claims abstract description 9
- 239000004568 cement Substances 0.000 claims description 6
- 239000010881 fly ash Substances 0.000 claims description 6
- 239000011268 mixed slurry Substances 0.000 claims description 3
- 239000007921 spray Substances 0.000 claims description 2
- 230000000694 effects Effects 0.000 abstract description 7
- 239000011435 rock Substances 0.000 abstract description 4
- 230000007547 defect Effects 0.000 abstract description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 7
- 238000010276 construction Methods 0.000 description 6
- 238000000926 separation method Methods 0.000 description 4
- 238000005507 spraying Methods 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 238000005065 mining Methods 0.000 description 2
- 239000011083 cement mortar Substances 0.000 description 1
- 230000005465 channeling Effects 0.000 description 1
- 239000012141 concentrate Substances 0.000 description 1
- 230000001276 controlling effect Effects 0.000 description 1
- 238000010291 electrical method Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 230000000877 morphologic effect Effects 0.000 description 1
- 238000005086 pumping Methods 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 230000002787 reinforcement Effects 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
- 238000012360 testing method Methods 0.000 description 1
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- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21F—SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
- E21F15/00—Methods or devices for placing filling-up materials in underground workings
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21F—SAFETY DEVICES, TRANSPORT, FILLING-UP, RESCUE, VENTILATION, OR DRAINING IN OR OF MINES OR TUNNELS
- E21F15/00—Methods or devices for placing filling-up materials in underground workings
- E21F15/08—Filling-up hydraulically or pneumatically
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/91—Use of waste materials as fillers for mortars or concrete
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- Engineering & Computer Science (AREA)
- Mining & Mineral Resources (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Geology (AREA)
- Consolidation Of Soil By Introduction Of Solidifying Substances Into Soil (AREA)
Abstract
The invention discloses a multi-layer-multi-angle old goaf grouting filling method. The method comprises the following steps: firstly, the distribution characteristics of old goafs and left coal pillars are cleaned; and then drilling the old goaf until the position near the basic roof rock stratum is stopped, putting a sleeve with an inclined elbow, putting a high-pressure hose with a self-advancing drill bit into the sleeve, taking down the self-advancing drill bit after the old goaf is reached, injecting filling slurry along a pipeline, changing the direction of the sleeve, repeating the self-drilling and grouting processes, and repeating the drilling process to treat the lower goaf after the upper goaf is treated. The invention solves the defects of small grouting filling range and poor filling effect of the existing old goaf, realizes multi-layer and multi-angle grouting by one-time drilling, and greatly reduces grouting cost while ensuring grouting effect.
Description
Technical Field
The invention belongs to the technical field of filling grouting, and particularly relates to a multi-layer-multi-angle old goaf grouting filling method.
Background
With the rapid development of cities and engineering construction in China, construction land is increasingly tense, and particularly resource-type cities, some civil buildings, industrial structures, traffic facilities and the like cannot be constructed or pass through an empty (dynamic) area due to non-land selection. In particular, in recent years, some cities have begun to build various large building (construction) structures above coal mining subsidence areas or to-be-mined areas in order to solve construction land bottlenecks and to concentrate land.
The primary development and utilization of the subsidence area is the treatment and construction of the subsidence area. Moreover, the amplitude staff of China are wide, the occurrence states of coal beds are quite different, and a plurality of subsidence areas are left after multi-coal-bed exploitation. At present, the goaf grouting reinforcement technology is most commonly used, holes are drilled from the ground to the goaf, and the prepared slurry is injected into the goaf after the holes are drilled to the preset positions.
Patent document (publication number CN 101021162) discloses a overlying strata separation grouting filling device and grouting filling system, the device can solve the problems that the existing overlying strata separation grouting filling technology has few grouting layers, can not perform continuous grouting and has low grouting efficiency, but needs to manufacture special sleeves in advance according to special stratum conditions, and has complicated operation steps and insufficient applicability and practicality. Patent literature (publication number CN103216236 a) discloses a method of reducing subsidence by grouting into a overburden bed of a stope, which is beneficial in controlling surface subsidence. However, this method is only suitable for the coal seam being mined, and is not suitable for the treatment of old goaf. Patent literature (publication number CN105804752 a) discloses a overburden separation grouting monitoring process in coal mining. The invention solves the problems of difficult grouting in a multilayer goaf and difficult searching of overlying strata of a separation layer, but the invention needs repeated drilling, has small grouting range and complicated grouting process.
In addition, most of the current grouting filling is single drilling from the ground to the goaf, reaching a preset position and beginning grouting. Because each drilling hole bears limited slurry amount, the filling range is smaller, and a plurality of dense drilling holes are often needed to be drilled in order to improve the filling effect, the grouting cost is greatly increased.
In summary, it is highly desirable to find a filling method capable of realizing one-time drilling, multi-layer and multi-direction overall grouting in an old goaf.
Disclosure of Invention
The invention provides a filling method for realizing multi-layer and multi-angle comprehensive grouting by drilling holes on an old goaf at one time, which aims to solve the technical problems of repeated drilling and successive grouting in the prior art.
In order to achieve the above purpose, the present invention is realized by the following technical scheme:
a multi-layer position-multi-angle old goaf grouting filling method comprises the following steps:
step 1: detecting the old goaf, and clearing the distribution characteristics of the old goaf and the left coal pillar;
step 2: drilling from the ground above the old goaf to the direction of the old goaf, and drilling a final hole to the vicinity of the basic top of the upper goaf;
step 3: a sleeve pipe with an inclined elbow is placed in a drill hole, the inclined elbow is in contact with the wall of the bottom of the drill hole, a high-pressure hose is placed in the sleeve pipe, the bottom of the high-pressure hose is connected with a self-advancing drill bit, forward hole jet flow of the self-advancing drill bit is used for breaking rock and drilling, a forward channel is provided for the jet drill bit, reverse hole jet flow is used for generating forward thrust, and an internal impeller plays a role in boosting so as to help the forward hole to generate larger pressure for breaking rock;
step 4: drilling the self-advancing drill bit to the upper goaf along the sleeve elbow direction until the self-advancing drill bit drills into the upper goaf, stopping drilling, taking down the self-advancing drill bit, starting grouting filling, and stopping grouting filling when the filling slurry starts to reversely spray from the high-pressure hose;
step 5: taking out the high-pressure hose, changing the direction of the sleeve, then lowering the high-pressure hose connected with the self-advancing drill bit in the sleeve, and repeating the step 4 until grouting filling of the upper goaf is finished;
step 6: and (3) continuing to drill downwards along the drilling direction of the step (2), drilling a final hole until the final hole reaches the vicinity of the basic top of the lower goaf, and repeating the steps (3) to (5) to finish grouting filling of the lower goaf.
Preferably, in the step 1, the old goaf is detected by a high-density electric method, a three-dimensional laser scanner or a method for determining the range of the old goaf described in the Chinese patent document with the grant publication number of CN104965229 a.
Preferably, the hole diameter of the drilled hole in the step 2 is phi 130mm.
Preferably, the deviation of the hole positions of the holes drilled in the step 2 is smaller than 1m, and the hole inclination is smaller than 1 degree.
Preferably, in the step 2, the final hole is drilled to a position which is 2-5m away from the basic top of the upper goaf.
Preferably, in the step 3, the diameter of the sleeve is phi 90mm, and the thickness of the wall of the sleeve is 8mm.
Preferably, the inclination angle of the inclined elbow in the step 3 is-51 degrees.
Preferably, in the step 3, the aperture of the high-pressure hose is phi 50mm, and the wall thickness of the hose is 4mm.
Preferably, the filling slurry in the step 4 is mixed slurry of cement and fly ash, and the weight ratio of the cement to the fly ash is 4:6.
Preferably, in the step 6, the final hole is drilled to a position which is 2-5m away from the basic top of the lower goaf.
Compared with the prior art, the invention has the following beneficial effects that
According to the invention, multi-layer and multi-angle comprehensive grouting is realized through one-time drilling, so that the defects of repeated drilling, sequential grouting, small grouting filling range and poor filling effect of the existing old goaf can be overcome, the grouting effect is ensured, the grouting cost is greatly reduced, and the treatment efficiency of the old goaf is improved.
Drawings
FIG. 1 is a schematic diagram of a multi-angle grouting flow in an upper goaf;
FIG. 2 is a schematic diagram of a multi-angle grouting flow in a lower goaf;
FIG. 3 is a top view of goaf grouting effect;
FIG. 4 is a schematic view of a self-advancing drill bit;
FIG. 5 is an enlarged schematic view of a borehole at an elbow;
FIG. 6 is a view showing the construction of the inside of the high-pressure pump house;
in the figure, 1, a water tank, 2, a high-pressure connecting hose, 3, a high-pressure pump station (3.1, a high-pressure pump, 3.2, a flow meter, 3.3 and a pressure meter), 4, a valve I, 5, a valve II, 6, a slurry stirring tank, 7, a drilling hole, 8, a sleeve, 9, a high-pressure hose, 10, an inclined sleeve elbow, 11, a self-advancing drill bit (11.1, a rear nozzle, 11.2, a front nozzle, 11.3 and an impeller), 12 and a goaf.
Detailed Description
The following examples are intended to illustrate and explain the invention adaptively and without limiting the scope of the invention.
For a clearer understanding of technical objects, features and effects of the present invention, the present invention will be further described in detail with reference to the accompanying drawings.
The invention provides a multi-layer-multi-angle old goaf grouting filling method, which comprises the following steps: the method comprises the steps of firstly, detecting an old goaf through a high-density electrical method, and finding out the distribution characteristics of the old goaf and the left coal pillar. Then, drilling the old goaf, drilling to the vicinity of the basic roof stratum, placing a sleeve with an inclined elbow, placing a high-pressure hose with a self-feeding drill bit in the sleeve, drilling the old goaf at high pressure along a certain angle, taking down the self-feeding drill bit after reaching the old goaf, injecting filling slurry along a pipeline, changing the sleeve direction, repeating the self-drilling and grouting processes, and repeating the drilling process after the upper goaf is treated, and treating the lower goaf.
As shown in fig. 1 to 6, the invention provides a multi-layer-multi-angle old goaf grouting filling method, which comprises the following specific implementation steps:
step 1: the distribution condition of the old goaf 12 of the to-be-constructed area is researched and ascertained by combining with the original geological technical data of the mine, and the morphological distribution map of the old goaf and the coal pillar group is drawn;
step 2: drilling a drilling hole 7 from the ground to an old goaf, drilling the drilling hole 7 to a complete bedrock section by 5m through a loose layer, then running a sleeve, fixing a pipe and protecting a wall by cement mortar, solidifying an orifice pipe, and then performing a pressurized water test, wherein the maximum pressure is not lower than 3MPa, so that no slurry channeling is ensured, and the final hole of the drilling hole 7 is positioned at the position of 2-5m above the basic top of the upper goaf; the aperture of the drilling hole 7 is phi 130mm, the hole position deviation is less than 1m, and the hole inclination is less than 1 degree;
step 3: a sleeve pipe 8 is put down in a drilling hole 7, an inclined sleeve pipe elbow 10 is connected to the bottom of the sleeve pipe 8, a high-pressure hose 9 is put in the sleeve pipe 8, a self-advancing drill bit 11 is connected to the head of the high-pressure hose 9, and a high-pressure pump station 3 is connected to the tail of the high-pressure hose 9; the aperture of the sleeve 8 is phi 90mm, the thickness of the pipe wall is 8mm, the inclination angle of the inclined sleeve elbow 10 is-51 degrees, the aperture of the high-pressure hose 9 is phi 50mm, and the thickness of the pipe wall is 4mm;
step 4: starting a valve number one 4, closing a valve number two 5, starting a high-pressure pump 3.1 in a high-pressure pump station 3, pumping water in a water tank 1 to a self-propelled drill bit 11 through a high-pressure connecting hose 2, enabling a high-pressure water impeller 11.3 to rotate to form horizontal torrent, spraying out rock in front of the broken drill bit from a front nozzle 11.2, and spraying out backwards from a rear nozzle 11.1 to drive the self-propelled drill bit 11 and a high-pressure hose 9 to drill into a goaf 12; the water pressure is regulated according to the flow meter 3.2 and the pressure meter 3.3, so that the water pressure is stabilized at about 3MPa, and the self-advancing drill bit 11 is continuously advanced;
step 5: when the drilling speed of the self-advancing drill bit 11 is obviously accelerated, whether the self-advancing drill bit 11 drills into the goaf 12 is checked according to the form and the drilling distance of the surveyed goaf;
step 6: after the self-feeding drill bit 11 is confirmed to be drilled into the goaf 12, the high-pressure pump 3.1 is closed, the valve I4 is closed, the self-feeding drill bit 11 is taken down, the valve II 5 is opened, the filling slurry which is stirred in advance is sent into the goaf 12 from the high-pressure hose 9 along a certain angle through the high-pressure pump station 3, the filling slurry is mixed slurry of cement and fly ash, and the weight ratio of the cement to the fly ash is 4:6; when the filling slurry is injected slowly and the back spraying condition exists in the high-pressure hose 9, stopping grouting and filling;
step 7: taking out the high-pressure hose 9, adjusting the angle of the sleeve 8, then lowering the high-pressure hose 9 connected with the self-advancing drill bit 11 in the sleeve 8, and repeating the operation processes of the steps 4 to 6 until grouting filling of the upper goaf is finished;
step 8: continuing to drill downwards along the direction of the drilling hole 7 in the step 2, and repeating the operation processes in the steps 3 to 7 until the final hole of the drilling hole 7 reaches the position of the basic top 2-5m of the lower goaf, thereby completing grouting filling of the lower goaf.
The foregoing is directed to the preferred embodiments of the present invention, and it should be noted that any modifications and enhancements made to the above-described embodiments of the present invention without departing from the true spirit and principles of the present invention.
Claims (10)
1. A multi-layer position-multi-angle old goaf grouting filling method is characterized by comprising the following steps of: the method comprises the following steps:
step 1: detecting the old goaf, and clearing the distribution characteristics of the old goaf and the left coal pillar;
step 2: drilling from the ground above the old goaf to the direction of the old goaf, and drilling a final hole to the vicinity of the basic top of the upper goaf;
step 3: a sleeve pipe with an inclined elbow is put down in the drilling hole, the inclined elbow is contacted with the hole wall at the bottom of the drilling hole, a high-pressure hose is put down in the sleeve pipe, and the bottom of the high-pressure hose is connected with a self-advancing drill bit;
step 4: drilling the self-advancing drill bit to the upper goaf along the sleeve elbow direction until the self-advancing drill bit drills into the upper goaf, stopping drilling, taking down the self-advancing drill bit, starting grouting filling, and stopping grouting filling when the filling slurry starts to reversely spray from the high-pressure hose;
step 5: taking out the high-pressure hose, changing the direction of the sleeve, then lowering the high-pressure hose connected with the self-advancing drill bit in the sleeve, and repeating the step 4 until grouting filling of the upper goaf is finished;
step 6: and (3) continuing to drill downwards along the drilling direction of the step (2), drilling a final hole until the final hole reaches the vicinity of the basic top of the lower goaf, and repeating the steps (3) to (5) to finish grouting filling of the lower goaf.
2. The method for grouting filling of the multi-layer-multi-angle old goaf, as claimed in claim 1, wherein the method comprises the following steps: in the step 1, the old goaf is detected by adopting a high-density electric method, a three-dimensional laser scanner or a method for determining the range of the old goaf described in Chinese patent text with an authorized bulletin number of CN 104965229A.
3. The method for grouting filling of the multi-layer-multi-angle old goaf, as claimed in claim 1, wherein the method comprises the following steps: the bore diameter of the drill hole in the step 2 is phi 130mm.
4. The method for grouting filling of the multi-layer-multi-angle old goaf, as claimed in claim 1, wherein the method comprises the following steps: and (2) the deviation of the hole positions of the drilled holes in the step (2) is smaller than 1m, and the hole inclination is smaller than 1 degree.
5. The method for grouting filling of the multi-layer-multi-angle old goaf, as claimed in claim 1, wherein the method comprises the following steps: and (2) drilling a final hole to a position which is 2-5m away from the basic top of the upper goaf.
6. The method for grouting filling of the multi-layer-multi-angle old goaf, as claimed in claim 1, wherein the method comprises the following steps: and in the step 3, the aperture of the sleeve is phi 90mm, and the thickness of the wall of the sleeve is 8mm.
7. The method for grouting filling of the multi-layer-multi-angle old goaf, as claimed in claim 1, wherein the method comprises the following steps: the inclination angle of the inclined elbow in the step 3 is-51 degrees.
8. The method for grouting filling of the multi-layer-multi-angle old goaf, as claimed in claim 1, wherein the method comprises the following steps: and in the step 3, the aperture of the high-pressure hose is phi 50mm, and the wall thickness of the hose is 4mm.
9. The method for grouting filling of the multi-layer-multi-angle old goaf, as claimed in claim 1, wherein the method comprises the following steps: the filling slurry in the step 4 is mixed slurry of cement and fly ash, and the weight ratio of the cement to the fly ash is 4:6.
10. The method for grouting filling of the multi-layer-multi-angle old goaf, as claimed in claim 1, wherein the method comprises the following steps: and (3) drilling a final hole in the step (6) to a position which is 2-5m away from the basic top of the lower goaf.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310401922.2A CN116357383A (en) | 2023-04-14 | 2023-04-14 | Multi-layer-multi-angle old goaf grouting filling method |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202310401922.2A CN116357383A (en) | 2023-04-14 | 2023-04-14 | Multi-layer-multi-angle old goaf grouting filling method |
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| CN116357383A true CN116357383A (en) | 2023-06-30 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117432463A (en) * | 2023-10-23 | 2024-01-23 | 中国矿业大学 | Parallel paste filling method |
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2023
- 2023-04-14 CN CN202310401922.2A patent/CN116357383A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117432463A (en) * | 2023-10-23 | 2024-01-23 | 中国矿业大学 | Parallel paste filling method |
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